Diamond ring



FIG. 1 is a perspective view of my new design relating to a diamond ring;

FIG. 2 is a side view of my new design, the opposite side view being a mirror image;

FIG. 3 is a front view of my new design, the rear view being a mirror image;

FIG. 4 is a top view of my new design; and,

FIG. 5 is a bottom view of my new design. 

I claim the ornamental design for a diamond ring, as shown and described. 